Mace, ISG and Sisk are battling it out for the contract to turn London's landmark Café Royal into a five-star luxury hotel. The deal is worth around £100m to transform the Café Royal into a luxury 25,000m2 hotel containing 160 rooms, spa and gym.

David Chipperfield Architects is currently putting the finishing touches to designs, with work due to start this summer and be finished ahead of the 2012 Olympics.

The three contractors are expecting to hear next week who has won the construction management deal. Mace is understood to be on site already overseeing enabling works, which could put the firm in pole position.

The new hotel is part of the Quadrant development, which is the biggest component of a £750m investment in redeveloping Regent Street.